An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. URLAUTH token forgery can occur via a missing mboxkey. If an attacker knew a folder name on the victim's account for which the victim had never issued an auth URL, they could forge a working URLAUTH token by computing an HMAC-SHA1 value with a predictable key, giving them read access to the mailbox. (URLAUTH is an obscure feature, meaning that the odds of any user actually being susceptible to this attack are very low. Perhaps no public clients use URLAUTH.)
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Thu, 16 Jul 2026 19:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Thu, 16 Jul 2026 18:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. URLAUTH token forgery can occur via a missing mboxkey. If an attacker knew a folder name on the victim's account for which the victim had never issued an auth URL, they could forge a working URLAUTH token by computing an HMAC-SHA1 value with a predictable key, giving them read access to the mailbox. (URLAUTH is an obscure feature, meaning that the odds of any user actually being susceptible to this attack are very low. Perhaps no public clients use URLAUTH.) | |
| First Time appeared |
Cyrusimap
Cyrusimap cyrus Imap |
|
| Weaknesses | CWE-340 | |
| CPEs | cpe:2.3:a:cyrusimap:cyrus_imap:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Cyrusimap
Cyrusimap cyrus Imap |
|
| References |
| |
| Metrics |
cvssV3_1
|
Projects
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Status: PUBLISHED
Assigner: mitre
Published:
Updated: 2026-07-16T18:54:53.528Z
Reserved: 2026-05-18T00:00:00.000Z
Link: CVE-2026-47085
Updated: 2026-07-16T18:54:47.753Z
No data.
No data.
OpenCVE Enrichment
Updated: 2026-07-16T19:30:05Z
Weaknesses